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This study investigates the escape of Mercury's sodium‐group ions (Na+‐group, including ions with m/q from 21 to 30 amu/e) and their dependence on true anomaly angle (TAA), that is, Mercury's orbital phase around the Sun, using measurements from MESSENGER. The measurements are categorized into solar wind, magnetosheath, and magnetosphere, and further divided into four TAA intervals. Na+‐group ions form escape plumes in the solar wind and magnetosheath, with higher fluxes along the solar wind's motional electric field. The total escape rates vary from 0.2 to 1 × 1025atoms/s with the magnetosheath being the main escaping region. These rates exhibit a TAA dependence, peaking near the perihelion and similar during Mercury's remaining orbit. Despite Mercury's tenuous exosphere, Na+‐group ions escape rate is comparable to other inner planets. This can be attributed to several processes, including that Na+‐group ions may include several ion species, efficient photoionization frequency for elements within Na‐group, etc. Atmospheric escape is defined as the loss of atmospheric particles in the form of neutrals and ions into outer space. Understanding atmospheric escape is a fundamental science question for studying the evolution of planetary atmosphere and habitability, as it can provide insight into how life can form on a planet. While atmospheric escape has been extensively studied in Venus, Earth, and Mars through in situ measurements and simulations, it remains poorly understood at Mercury. In this study, we investigate the escape of the most abundant heavy ions at Mercury, specifically the Na+‐group ions, using MESSENGER's measurements. Our findings show that the escape rates of the Na+‐group ions are dependent on Mercury's orbital phase around the Sun, exhibiting a seasonal effect with rates from 0.2 to 1 × 1025atoms/s. This rate is comparable to the ion's escape rates at other inner planets, which is surprising given that Mercury only has a tenuous exosphere. We propose that this can be attributed to several processes such as efficient photoionization, solar wind sputtering, and solar wind momentum exchange at Mercury, and the Na+‐group ions include several ion species such as Na+, aluminum ion (Al+), silicon ion (Si+) and magnesium ion (Mg+) etc. Na+‐group ions form escape plumes in solar wind and magnetosheath, with higher fluxes in the positive solar wind electric field hemisphereThe escape rate ranges from 0.2 to 1 × 1025atoms/s, with the magnetosheath being the main escaping regionEscape rates peak near perihelion, and are similar during other true anomaly angle (TAA) intervals Na+‐group ions form escape plumes in solar wind and magnetosheath, with higher fluxes in the positive solar wind electric field hemisphere The escape rate ranges from 0.2 to 1 × 1025atoms/s, with the magnetosheath being the main escaping region Escape rates peak near perihelion, and are similar during other true anomaly angle (TAA) intervals

Sheep and goat dairy products are part of the culinary tradition of most European countries. The paper explores consumers' perceptions and attitudes towards sheep and goat dairy products within seven European countries. A combination of focus group discussions and laddering interviews were used. Results showed that most consumers perceived those products as a speciality food with a unique taste that can be perceived as good or bad. Perceived quality, naturality and healthiness are the dominant motivational structures, while value-for-money is a secondary concern. More focus on communicating the hedonic dimension and positive health-related messages may increase consumers’ interest and acceptance.

The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) observations of the seasonal variability of Mercury's Ca exosphere are consistent with the general idea that the Ca atoms originate from the bombardment of the surface by particles from comet 2P/Encke. The generating mechanism is believed to be a combination of different processes including the release of atomic and molecular surface particles and the photodissociation of exospheric molecules. Considering different generation and loss mechanisms, we perform simulations with a 3‐D Monte Carlo model based on the exosphere generation model by Mura et al. (2009). We present for the first time the 3‐D spatial distribution of the CaO and Ca exospheres generated through the process of micrometeoroid impact vaporization, and we show that the morphology of the latter is consistent with the available MESSENGER/Mercury Atmospheric and Surface Composition Spectrometer observations. The results presented in this paper can be useful in the exosphere observations planning for BepiColombo, the upcoming European Space Agency‐Japanese Aerospace Exploration Agency mission to Mercury. A seasonal MIV‐generated CaO exosphere with maximum density above the dawnside‐nightside hemisphere of Mercury is expectedAn exospheric energetic Ca component, derived from the dissociative ionization and neutralization of CaO, is expected above the same regionSimulated Ca distribution in good agreement with the MESSENGER observations; the derived emission rate is up to 1/10 of the observed one

At Mercury, several processes can release ions and neutrals out of the planet's surface. Here we present enhancements of planetary ions (Na+‐group ions) in Mercury's northern magnetospheric cusp during flux transfer event (FTE) “showers.” FTE showers are intervals of intense dayside magnetopause reconnection, during which FTEs are observed in quick succession, that is, only separated by a few seconds. This study identifies 1953 FTE shower intervals and 1795 Non‐FTE shower intervals. During the shower intervals, this study shows that the FTEs form a solar wind entry layer equatorward of the northern magnetospheric cusp. In this entry layer, solar wind ions are accelerated and move downward (i.e., planetward) toward the cusp, which sputter upward‐moving planetary ions with a particle flux of 1 × 1011m−2s−1within 1 min. The precipitation rate is estimated to increase by an order of magnitude during FTE showers, to 2 × 1025s−1, and the neutral density of the exosphere could vary by >10% in response to this FTE‐driven sputtering. Such rapid large‐scale variations driven by dayside reconnection may explain the minute‐to‐minute changes in Mercury's exosphere, especially on the high latitudes, observed by ground‐based telescopes on Earth. Our MESSENGER in situ observation of enhanced planetary ions in the entry layer likely corresponds to an escape channel for Mercury's planetary ions. Comprehensive, future multipoint measurements made by BepiColombo will greatly enhance our understanding of the processes contributing to Mercury's dynamic exosphere and magnetosphere. For the airless objects in the solar system, energetic ion sputtering is an important process that can release particles out of the planet's surface. In Mercury's magnetosphere, the solar wind energetic ions have been suggested to be able to release neutrals out of the surface in a short period by models and simulations. This paper has examined the 4 years of magnetic field and plasma measurements collected by NASA's MESSENGER mission orbiting Mercury and has led to the discovery of how reconnection between the interplanetary and planetary magnetic fields leads to the formation of solar wind entry layers around Mercury's magnetospheric cusps. These entry layers act as magnetic channels that cause the solar wind energetic ions to move downward toward the planet and precipitate onto the surface beneath Mercury's northern and southern magnetospheric cusps where they sputter neutral sodium and sodium ions. This paper concludes that the solar wind sputtering could account for 10% or greater changes in the density of neutral sodium in Mercury's exosphere, and the sputtered sodium ions likely form an escape channel of Mercury's planetary species. The ion escape depended on the solar wind driving magnetopause reconnection at Mercury is different from the ion escape at Venus and Mars, where escape ions are ionized by the solar ultraviolet (UV). Solar wind entry layer is observed to form equatorward of cusp during flux transfer event showers which enhances precipitation rate by an order of magnitudeSolar wind sputtering can release planetary ions and neutrals efficiently within 1 min of the onset of magnetopause reconnectionA new escape channel for planetary ions is formed by solar wind sputtering with an escape rate of ∼1024s−1for Na+‐group ions Solar wind entry layer is observed to form equatorward of cusp during flux transfer event showers which enhances precipitation rate by an order of magnitude Solar wind sputtering can release planetary ions and neutrals efficiently within 1 min of the onset of magnetopause reconnection A new escape channel for planetary ions is formed by solar wind sputtering with an escape rate of ∼1024s−1for Na+‐group ions

After the Second World War, modern agriculture and urbanisation have contributed to the vanishing of many traditional landscapes. Over the last years, agricultural restructuring, changes in farms’ structure and crisis in modern agriculture have led to an increasingly diverse set of relationships between land management and land ownership. This is especially true in peri-urban areas, where farmlands are often converted from commercially driven agriculture to various and highly dynamic land uses. This paper presents a micro-sociological study carried out in a municipality close to Pisa, where two types of landscape coexist: an urbanised lowland including areas of mechanised agriculture and a hilly area preserving traditional Mediterranean elements – such as terraces and ancient wine caves – which was abandoned during the rural outmigration and is currently being restored and managed by hobby farmers. Unlike lowland landowners, hobby farmers frame their “dwelling” on moral discourses and see the upland as a cultural heritage rather than as a personal ownership of productive units of land. Drawing on qualitative interviews and other sources of evidence, this paper analyses the landowners’ motivations and practices in the two areas and explores some of the implications of this landscape polarisation within the municipality borders for landscape management and planning.

Abstract: By using theoretical models of plasma dynamics, it is possible to reconstruct the evolution of many magnetospheric processes; nevertheless, these models need the support of both electric and magnetic field models, and they can simulate known processes only. Conversely, the empirical models are mainly based on statistical analysis; hence, they start from observations, not from processes. Statistical analyses and the derived empirical models are important complements to theoretical models and simulations since the former represent the actual conditions. The empirical models of the inner magnetosphere ion distribution MODEM and of the pitch angle distribution PADEM have proved to be successful in deriving average features of the ring current as well as in obtaining the long-term development of the ion distributions during quiet and disturbed periods. The major goals of this approach are: (1) the description of the equatorial proton population during quiet times and the quantitative characterization of their spatial and energetic distribution; (2) the evidence of some key features of the proton distribution strictly connected to the solar wind characteristics; (3) the investigation of the evolution of magnetospheric ion populations during geomagnetic disturbances and their role in the ring current development. In this paper we review the above-mentioned studies.

The ion flux spectra as observed by AMPTE-CCE/CHEM have been averaged over more than two years, and organized as a function of energy, L-shell, magnetic local time and pitch angle. The obtained data set has been best fit with an appropriate multi-parametric function. This preliminary study deals with 90° pitch angle proton distributions, during low geomagnetic activity. The resulting model distributions are presented and compared to the input distributions. The significance of the model parameters with respect to the ring current properties is discussed, with particular attention on the ion flow pattern characteristics.